The present invention relates to apparatus for cleaning transmission and pipelines in situ underground, and more particularly to such apparatus which also is capable of performing additional functions associated with transmission lines or pipelines in situ underground.
It is common practice to provide pipelines or transmission lines with exterior coating as the pipelines or transmission lines are positioned in the earth's surface to inhibit corrosion and electrolytic action which might deteriorate the pipes sufficiently to eventually cause a rupture or break therein. However, interior coating of a pipe is now accomplished by various methods including joint-by-joint coating prior to the time that the joints are coupled together and lowered into the earth's surface. Other methods now used employ techniques in which the transmission line or pipe may be cleaned and coated while in situ. However, such methods and techniques have various disadvantages such that they are not efficient for commercial and practical exploitation.